In 1762, John Montagu, the fourth Earl of Sandwich, had his hands full, literally. As First Sea Lord, he commanded the mighty British Navy, was a noted explorer, and also a dedicated gambler with a love of day long card games.

This led to little time for food, so he came up with the ingenious idea (some say at the card table) of putting meat between two slices of bread. From then on it did not...